In order to describe fully the complete conquest which the iron horse has accomplished in British India, volumes would be required. In that country the steel highway has been driven forward in the face of prodigious difficulties of every description; the story is an exciting romance.

But the features which impress the traveller most strongly are the bridges. Some compel more than passing interest because of their great length, such as the Sone bridge, on the East Indian railway, which consists of 93 spans, giving the structure a total length of 10,952 feet, making it one of the longest bridges in the world; or the Godavari over the river of the same name on the Madras North-East line, 9,066 feet in length; others because of their height, as, for instance, the Gokteik Viaduct in Burma, 325 feet high; or the Dhorabhave Viaduct, 178 feet above the stream; while here and there attention is challenged because of the massive proportions of the structure or its unusual design, as, for instance, the Jubilee Bridge across the river Hooghly at Naihati, or the Lansdowne Bridge across the Indus at Sukkur, the main span of which is 790 feet clear.

It may be safe to assert that no country has offered the bridge-builder such striking opportunities to display his ability or enterprise as the Indian Empire. The Americans point to the great width of their waterways, and the huge structures which leap across the Mississippi, Missouri or Columbia rivers, but, compared beside the erections which carry the railway across the Indian waterways, they appear puny.

The Indian rivers are famous for their great width, and the extent to which they break up the country through which they make their tortuous ways to the sea. The result is that when the engineer is called upon to cross from bank to bank, especially in connection with the more important waterways, he is faced with some teasing and complex problems, to solve which demands often considerable ingenuity and the expenditure of much racking cogitation. These rivers are bad friends to the engineer at the best of times, but when lashed into fury and swelled to flood they almost defy mastery.

The flood is the bugbear of the bridge-builder. One never knows what the enraged water is going to do next. Sir Bradford Leslie, K.C.I.E., M.INST.C.E., who probably has been associated with more great engineering achievements of this character in India than any other living engineer, can recall thrilling moments innumerable. For instance, when he was carrying the Jubilee Bridge across the river Hooghly, the water carried away one of the caissons which he was about to launch for one of the piers. He thought it had been lashed safely into position by means of chains, preparatory to sinking, but the Hooghly “bore” quickly undeceived him. The Hooghly bore is an ugly customer, for at times it attains a height of 7 feet, and travels up-stream for 70 miles in four hours. This rapidly-moving bank of liquid struck the unlucky caisson, although the latter was of respectable dimensions and weight, snapped the mooring chains as if they were pack-thread, and carried the cylinder away as if it were a small butter-tub. The engineer had a lively chase up-stream after his work, and finally secured it stranded in an awkward position about half-a-mile above its site.

Immediately arrangements were hurried forward to salvage the caisson. After a day and a half’s continuous hard toil it was recovered and anchored alongside the bank until the next propitious moment arrived for it to be towed out into the stream and sunk into position.

In the early days the engineers in their bridge-building operations suffered the maximum width of a river to dictate what the length of such a structure should be. Seeing that the normal channels of many of these waterways are narrow in comparison with what they attain under flood, this rendered bridge-work exceedingly expensive and intricate. It is no uncommon circumstance for a waterway, when swollen by the rains of the wet season, to spread out for a width of three miles or more. It becomes practically insatiable, the soft earth forming the banks falling a ready victim to the powerful eroding action of the scurrying water. The result is worse than that brought about by the scouring of the River Mississippi, which devours huge masses of land continually on either bank. When the Indian river falls, unsightly stretches of undulating sandbanks are revealed, riven by little back channels and small lagoons, which present a general aspect of desolation. Under such circumstances, bridging from bank to bank is a somewhat vague undertaking, for the simple reason that it is difficult to decide what are the limits of the waterway, because erosion continues until the water reaches material which defies this action.

The engineer has met this situation now in an ingenious manner. He determines the channel of the river and keeps it within bounds by means of an artificial wall or training-bund, which is carried parallel with the navigable channel, the flow of water through the space between the inner side of the wall and the shore being obstructed by a solid embankment which carries the track. This system was employed first by Mr. J. B. Bell to carry the North-Western State railway across the Chenab River at Sher Shah, and proved so eminently successful that it has come into general favour.

One of the latest and most interesting, as well as largest undertakings of this class, is that in connection with the Curzon railway bridge over the Ganges at Allahabad, for the Allahabad-Fyzerbad railway. At this point the river flows between high banks of hard clay about 3 miles apart, and so resistant is this earth to scouring action that erosion has been brought to cessation practically. The width of the waterway, however, is about 1¼ miles, and when it was decided to span the river, a great length of steel appeared inevitable.

The engineer-in-chief for the work, Mr. Robert R. Gales, M.INST.C.E., however, decided to cut down the length of the bridge-work to 3000 feet. The project was examined at great length, owing to the fact that the difference in the level of the river during the dry and flood seasons is not less than 31 feet, as the Ganges receives the waters of the Jumna about 7 miles above the site selected for the crossing. Careful investigations, however, pointed to the fact that the accumulated waters could be directed safely through a channel some 3000 feet wide, and accordingly the erection of the training-bund was taken in hand on the left bank. It measures some 4000 feet in length from end to end, and the top is 5 feet above the flood-level of the river. The up-stream arm measures 3,300 feet in length, and the extremity ends in a sharp curve to mitigate the effects of scouring. Viewed from the bank, the work resembles a huge letter “L,” with the bottom arm pointing up-stream, and the tail overhanging for about 700 feet, while the upright member forms the embankment connecting the training-wall to the shore, and leads the railway track to the bridge.

The training-wall is built up of sandy soil, with stone pitched on the face exposed to the action of the river. At the top it is about 20 feet in width, and carries a wide-gauge railway track from end to end, so that should the floods tear a gap in the embankment, the injury can be repaired immediately by dumping spoil into the breach from railway wagons.

Erection had to be hurried forward, as the season available for operations was so short. In view of the fact that the erection of the wall entailed the handling of some 50,000,000 cubic yards of earth, some idea of the magnitude of the task may be gathered. It was split up into a number of contracts, and when the operations were in full swing no less than 7000 coolies found employment.

While this work was in progress the bridge itself was pushed forward. The length of metal is 3000 feet, divided into 15 spans, each of 200 feet, carried upon masonry piers. The bridge was called upon to meet requirements not only for railway traffic but for pedestrians and vehicles as well. A single line of 5 feet 6 inches gauge suffices for the former, which is carried upon the bottom deck, while the upper deck meets the second requisition, being 23 feet wide and about 60 feet above the level of the waterway when in flood.

The undertaking was pushed forward with such energy that it was completed in three seasons. The saving in outlay resulting from constricting the river channel, and thereby reducing the length of steel-work, represented no less than £100,000, or $500,000. This offers a convincing illustration as to the ingenious manner in which the bridge engineer in India has succeeded in reducing the costs of spanning the noble waterways of the country.

In a far-away corner of the same country, Upper Burma, may be seen another interesting example of the bridge-builder’s craft, carried out under particularly exacting conditions in a forbidding country. This is the Gokteik Viaduct, which carries the metre-gauge single track of the Burma Railway Company across the gorge of the same name. This structure was completed by the Pennsylvania Steel Company, of Steelton, Pennsylvania, and the award of the contract was criticised severely in Great Britain. But the Government wanted the valley spanned in the shortest possible space of time and at a moderate price. When the tenders invited from all parts of the world were opened, it was found that the British firms had been outclassed by their American rivals in both these essential factors.

The location of the railway across this gorge was beset with peculiar difficulties. The question of the approach was trying to decide to the best advantage, and in fact so many surveys were made that one of the American engineers remarked “that he could not see the side of the cliff for survey pegs.”

The gorge itself is also somewhat strange; in fact, it is a curious wonder of Nature. The Chungzoune River flows through the rift, but out of sight, its course being through a natural tunnel, into which it disappears suddenly at a depth of 500 feet. When the line was first surveyed it was in accordance with a low viaduct, the approach thereto being over a suggested section of rack railway working on the Abt system, with grades of 1 in 12½. This was subsequently abandoned, and the surveyor was called upon to find a fresh location so as to eliminate the rack railway, and to give grades not exceeding 1 in 25, so as to permit the line to be worked by adhesion. This decision raised the height of the towers by 70 feet and increased its length to 1,350 feet. Even this did not meet with approval, for after prolonged deliberation a third location was demanded, to give an easier line yet. In this last survey the gradients were flattened to 1 in 40, with an attendant increase in the height of the structure as well as of its length. It was found impossible to improve upon the viaduct itself, so further surveys were carried out to improve the approaches, reducing their length and introducing curves at either end of the viaduct.

At last finality was reached, and the contract was secured by the American bridge-builders on April 28, 1899. They lost no time in hurrying forward the preparation of the steel. Three months later a special train of 45 cars, laden with 977 tons, left Steelton on the 201-miles run to New York, where a specially chartered steamer was in waiting to receive this steel cargo. The vessel left the American port on a journey of over 10,000 miles to Rangoon, where the freight was transferred to the small trucks of the railway and sent on the up-country journey of 460 miles to the Gokteik gorge. No less than three steamers were required to transport the 4,308 tons of steel, together with some 200 tons of requisite tackle for erection, and 35 American bridge-erectors.

When the Americans arrived on the scene they were treated to their first experience of Indian weather. The rain fell in torrents; the roads were converted into rushing streams, and the low-lying stretches of land into lakes. This was something new to the Americans, and they chafed at being compelled to sit down to wait until the weather moderated. To make matters worse, the line was knocked about severely by the rain, no less than thirteen wash-outs occurring between the coast and the gorge. In one place a locomotive got caught. It could not advance and could not retreat, owing to breaches in the railway on either side, so quietly settled down to rest in the waterlogged embankment, and finally slipped into a field of rice, to the intense disgust of the owner.

The result was that the port became congested with the steel and tackle awaiting dispatch up-country. The railway company repaired the wash-outs with all possible speed, and directly the line was opened the material poured towards Gokteik in a ceaseless stream. In fact, the American engineers were somewhat perplexed by the speed with which the material was sent up, and they had a spirited task in sorting out the pieces of steel as they arrived. The work proceeded so feverishly that the empty trains could not be backed out of the shunting-yard with sufficient alacrity to admit incoming loads. The bridge-builders extended assistance in a novel manner. Shunting was abandoned. The large steam derricks picked up the empty cars bodily off the one track, whipped them round, and deposited them upon a siding, from which the engines pulled them out as best they could.

The railway company provided the builders with a special railway down the side of the cliff, as the approach was not completed. This was a huge switch-back, where the trains ran from side to side, first forwards and then backwards. The descent of the precipice in this manner treated the bridge-builders to an exciting ride, which somewhat unnerved them at first, as it was far and away too thrilling to be pleasant. A cableway was also stretched across the gulch, and this was used for transporting material from point to point. In fact, two locomotives were dismantled and sent across this rope in pieces to be re-erected on the opposite side.

When the bridge-builders arrived they found that Mr. G. Deuchars, the engineer-in-chief to the railway, had completed the whole of the preparations. The concrete pedestals for the steel towers stretched across the floor of the ridge in two unbroken lines over the top of the natural bridge through which the Chungzoune River makes its subterranean way. All that the bridge-builders had to do was to set the steel.

The viaduct was built upon the overhanging principle, in accordance with the American practice, by means of a traveller. This was a cumbersome piece of apparatus weighing 100 tons, with a long arm which reached out over the gorge from tower to tower. To the native this appliance was a source of infinite wonder. When it was pushed out to its fullest extent, and the long arm appeared certain to lose its balance and to topple into the ravine, they looked on with awe; and when the Americans flew in the face of Providence, as they thought, by venturing to the outermost point to carry out their work, they shuddered. In fact, they never became accustomed to that traveller. Why it did not capsize exceeded their comprehension.

The American workmen were assisted in their operations by 350 natives brought from other parts of the country, and who were accustomed somewhat to bridge-building. Once work was brought into swing, it went forward with a rush, the steel towers springing up from their pedestals to a height of 200 feet or so within two or three days. The men toiled 9¾ hours every day, and there was not a halt except when the monsoon blew and it was well-nigh impossible to secure a foothold in exposed positions, or when the torrential rainfall prevailed.

The white men found the heat particularly trying and exhausting. Those perched 200 or 300 feet in the air, and fully exposed to the sun and a temperature of 120 degrees, secured a little welcome shade under an awning that was stretched over the apparatus. They wore the lightest of clothing, while white pith helmets served to offer some protection from sunstroke.

The total length of the work is 2,260 feet, and it is built up to 10 spans, each measuring 120 feet, and 7 spans of 60 feet apiece. The girders forming the deck are supported on steel towers spaced 40 feet apart. The height of the rails at the highest pier is 325 feet above the floor of the gorge, and 825 feet above the Chungzoune stream. No less than 232,868 separate pieces of steel had to be handled on the site, and the natives had to drive 200,000 rivets to secure the fabric together.

Owing to the remote point at which work was being carried out—10,000 miles by sea from home—an elaborate cable code was drawn up, each integral part of the viaduct, as well as details of the erecting plant, having a distinctive word. In addition, there were special words for the purpose of reporting the progress of the erection to headquarters. Every week the chief engineer cabled home a full progress report at a cost of 5s., or $1.25, per word. The men were provided with a well-equipped medicine chest, and a complete photographic outfit constituted an important part of the organisation, photographs being dispatched to Steelton regularly to supplement the cabled and written report on the progress of the undertaking. Only one man was lost in the enterprise, and this was attributable to fever produced from indulgence in alcoholic liquor. No other fatality was recorded either among the natives or Americans, and no serious accident marred the work, which, bearing in mind its magnitude and character, was highly satisfactory.

The actual erection occupied nine months, work being continued uninterruptedly through the wet season, when, fortunately, the greater part of the annual 150 to 200 inches of rain fell during the night. Although the viaduct is 24½ feet wide across the top, which is sufficient to carry a double track, only one road is laid at present. The bridge also enables pedestrians to cross from one side of the chasm to the other, refuge platforms being provided at frequent intervals to enable those afoot to escape being run down by passing trains. Upon completion, the structure was subjected to severe tests spread over a period of two months, and these proving satisfactory, the structure was accepted by the railway authorities. The mammoth steel traveller weighing 100 tons, and which had played such an important part in the rapid erection of the viaduct, was demolished and sold for scrap.

By the provision of this viaduct at the selected height the track is led to a natural ledge on the opposite cliff-face. While the viaduct was under construction the railhead was pushed forward, the material for the grade being transported across the valley by the overhead cable. By the time trains were able to cross the structure, the end of steel had reached a point some 35 miles beyond.

Although the viaduct is not so lofty as other structures of its class in other parts of the world, yet it occupies a position of distinct importance. Moreover, it constitutes one of the finest expressions of this class of American work that has ever been fulfilled.